1. Field of the Invention
The invention relates to guidance systems for farm equipment, such as tractors.
2. Description of the Prior Art
Automatic guidance systems for following furrows for crops or the like are well known in the art. Such systems control the movement of the tractor or the like so that correction may be made to the vehicle in response to guide means engaging the furrows. Certain of these systems do not compensate when the guide means comes out of alignment with a previously ploughed furrow, such as U.S. Pat. No. 1,390,419 to Zybach. In U.S. Pat. Nos. 3,537,531 and 3,402,784, although these systems are directed to overcompensation, the power steering system of the vehicle is not controlled. Other systems, such as the system described in U.S. Pat. No. 3,844,372, are quite complicated and rely on a combination of proportioning switches to correct for oversteering and have not been generally successful.
It can be seen that no prior art patent shows a direct hook-up of the guide means to the power steering pumps of the vehicle. Thus, there is no prior art system which allows a tractor or the like to follow accurately a straight line from open field through to harvest in any row crop.